Effects of Multi-Sensor Radar and Rain Gauge Data on Hydrologic Modeling in Relatively Flat Terrain

• Other Authors: Martinaitis, Steven Michael (authoraut)
• Format: Others
• Language: English; English
• Published: Florida State University
• Subjects: Oceanography; Atmospheric sciences; Meteorology
• Online Access: http://purl.flvc.org/fsu/fd/FSU_migr_etd-2696

This study evaluates the impacts of two different precipitation types on stage heights from a fully integrated and distributed, physically based hydrologic model - MIKE SHE. Simulations using a network of South Florida Water Management District (SFWMD) rain gauge measurements in the form of Thiessen polygons are compared with those using a &126; 4 x 4 km gridded historical precipitation database prepared at Florida State University (FSU). The FSU procedure employs a version of the National Weather Service (NWS) Multi-sensor Precipitation Estimator (MPE) algorithm. Each precipitation input is at both hourly and daily intervals. Simulated stages from MIKE SHE are evaluated over the relatively flat Big Cypress Basin (BCB) which has a maximum elevation range of &126; 12.5 m over a 1661 km&178; area. Daily averaged stage heights are analyzed at four stream gauge sites along canals within the BCB using seasonally based three-month model runs between 2003 to 2005 plus two separate case studies containing significant rainfall accumulations. Results show a high correlation between precipitation values of the FSU MPE database and the SFWMD rain gauges because the rain gauge data are incorporated into the MPE algorithm. Therefore, stage hydrographs and statistical properties of the stages generally are very similar between the two precipitation datasets at both temporal resolutions. Slightly greater differences are found between observed stages and those from the four versions of modeled output. The high resolution FSU MPE precipitation estimates generally provide improved stages compared to the SFWMD rain gauges. The use of hourly temporal resolution input impacts the timing and magnitude of the resulting stages. The modeled stages based on hourly precipitation values generally provide a faster hydrologic response and better simulate the observed stages than do daily values during extreme rainfall events (e.g., Hurricane Wilma). We believe that improved multi-sensor products and quality control procedures can be beneficial to enhancing water management decisions and flood forecasting within the SFWMD. === A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science. === Fall Semester, 2008. === November 6, 2008. === Precipitation Comparison, Watershed Management === Includes bibliographical references. === Henry E. Fuelberg, Professor Directing Thesis; Phillip Cunningham, Committee Member; Guosheng Liu, Committee Member; Chandra S. Pathak, Committee Member.